the Main South Line and eventually terminates at the Christchurch Southern Motorway (SH 76). Route changes Over the past 40 years SH 73 has been subjected to several route changes both in the Christchurch and the Arthur's Pass-Otira areas. In the early years SH 73 originally ended at the Blenheim Road and Hansons Lane corner in Upper Riccarton. In 1999, one of the worst sections of highway in the country (around Candy's Bend) were replaced with the Otira Viaduct. Meanwhile, in Christchurch, since SH 1 was rerouted to bypass the CBD, SH 73 was extended to Brougham Street/Waltham Road intersection, with the rest of the route covered by SH 74. In 2004, with SH 74 being rerouted to run along the Ring Road and the entire length of Tunnel Road instead of through the CBD, SH 73 was extended further to the Port Hills Road interchange on SH 74. It was also rerouted from the intersection of Blenheim Road to follow Curletts Road and Yaldhurst Road, instead of via Main South Road through Hornby, meeting back again with SH 1 at the intersection of Masham and Russley Roads. As of December 2012, with the extension of the Christchurch Southern Motorway, the section of SH 73 east of Curletts Road was re-gazetted as SH 76 in line with the new motorway extension. Former spur sections State Highway 73A was a spur section of SH 73 connecting the suburbs of Hornby, New Zealand and Sockburn, New Zealand via Main South Road and Blenheim Road. Before 2004 it formed part of the old route of SH 73 and further before that SH 1. It was one of the few state highways in New Zealand to be wholly dual carriageway. In 2014, the entire highway has been revoked due to completion of the Christchurch Southern Motorway (gazetted SH 76 in 2012) which runs almost parallel to this route. Major junctions See also List of New Zealand state highways References External links New Zealand Transport Agency Great Alpine Highway - a tourist site promoting the road State Highway 73 at Google Maps 73 Transport in Canterbury, New Zealand